Add love.data module.

- Moved love.math.compress / decompress / decode / encode / hash to love.data.
- Changed love.data.compress/decompress to take the format argument first instead of second.
- Added love.data.newDataView. Returns a read-only subsection of an existing Data object.
- Added love.data.newByteData. Mostly useful in combination with LuaJIT's FFI as it has no extra methods currently.
- Added implementations of Lua 5.3's data packing APIs: love.data.packString / packData / unpack / getPackedSize.

Resolves issue #1336.
Resolves issue #1331.

--HG--
branch : minor

src/scripts/nogame.lua

@@ -923,7 +923,7 @@ function love.nogame()
 		love.graphics.setBackgroundColor(136/255, 193/255, 206/255)
 
 		local function load_image(file, name, flags)
-			local decoded = love.math.decode("base64", file)
+			local decoded = love.data.decode("base64", file)
 			return love.graphics.newImage(love.filesystem.newFileData(decoded, name:gsub("_", ".")), flags)
 		end